“Recently, an annual convention of the American Scientific and Technical Society of Mechanics was held. At this congress, reports of the most prominent aircraft designers on the subject “Aviation in five years” were heard. These reports, built on the basis of current trends in the development of aviation, have drawn a really interesting and majestic picture of air conquest in the near future. Here, not only the possible sizes of the 1942 aircraft of the year were predicted, but also the design of aircraft engines, the economics of operation (as in the text - VO), the amenities for passengers, the control and stability of the aircraft, the achievement of higher flight speeds, as well as the development of the most difficult transoceanic airways.
Modern aircraft are the fruit of long-term engineering work and a complex production process. For the creation of an original, constructive new machine, it takes years. Therefore, the predictions of American specialists placed below are not a prophecy, but rather the opening of that veil that carefully conceals their work on designing future aircraft.
Stopping on the further development of aircraft engines with spark ignition, the speakers believe that, based on the state-of-the-art technology, the capacity of air-cooled motors may exceed 1500 l. with. while reducing the specific weight of the motor. In five years, the standard aircraft engine will weigh 0,4 kg per horse. force Even the modern 24-cylinder Nepir engine that develops the 725 l. with. at the height of 1 000 m, subject to increasing the number of revolutions and increasing the compression ratio could give power in 1 400 l. with. Soon, engines with small but numerous cylinders should win a decisive victory over engines with large cylinders due to the development of more power with the same weight. For example, a thirty-liter engine can develop in the presence of 60 cylinders 1 800 l. with. Naturally, the increase in engine power in the future will require a significant reduction in its specific weight, although, at the same time, the number and weight of auxiliary mechanisms will increase.
Future aircraft engines will be predominantly air cooled, which greatly simplifies the design of the entire power plant. On the other hand, air cooling with an increase in motor power leads to an increase in drag caused by enhanced circulation of air flow in the cooling system. For this reason, for aircraft engines with power over 1 000 l. with. liquid cooling will be used, which has the advantage that the useful surface of the cooling system can be increased without restrictions and at the same time without increasing air resistance.
Specific fuel consumption should be reduced, mainly due to the use of fuel with a high octane rating. Since the term "octane number" is relatively new and therefore unknown to our readers, we give a brief explanation of it. The octane number is an abstract numerical value obtained by comparing the degree of detonation of the test fuel with the control fuel consisting of a mixture of iso-octane and heptane. Iso-octane (С8 Н18) is characterized by low detonation and, in determining octane number, is taken for detonation as 103%. Normal heptane (С7 Н16) is distinguished by high detonation and is accepted when tested on an experimental motor as 0%. The octane number is the percentage of iso-octane in this control iso-octane-heptane mixture.
At present, the production of fuel in 100 octane is already established in small sizes - in a few years it will be as common in aviation as the best fuel in octane in 87. Now in American laboratories, fuel equivalent to 130 octanes, which contains mixtures of gasoline and synthetic mixtures of purified industrial gases, is being studied. This new type of fuel, which will be burned with the least possible degree of compression, but with maximum supercharging, will sharply increase the engine's power and, thus, reduce its specific weight. The specific fuel consumption in an aviation engine in five years will be less than 160 grams per 1 l. with. per hour instead of modern 200 g with a compression ratio of 6 — 6,5.
Renowned designer Sikorsky believes that even before 1950, it would be possible to build flying boats weighing 500 tons, designed for 1 000 passengers. But since the size of the aircraft is limited by the length of the route, the possibility of building giant air express trains on 1 000 passengers is very doubtful. In any case, in five years the weight of the largest aircraft will exceed 100 tons.
Already, at present, over the length of the air route over 7 000 km, the commercial load in 10% of the total weight of the aircraft has been almost reached. Modern aircraft could have an even greater load if they had sufficient internal usable volume. In the future, very large aircraft will be built that have the best performance in relation to the total weight. With increasing dimensions, the frontal resistance of the aircraft varies slightly less than the square of its linear dimensions, while the weight increases in a cube. As a result, each unit of volume of a large aircraft requires less engine power than a small one.
The types of aircraft now defined will exist in five years, however, the difference in their quality indicators will be greatly reduced. The size of the aircraft will increase so that the flying boats will approach the land aircraft, which are still considered the most effective. On transoceanic paths, it is precisely flying boats that should receive preference not only because of the possibility of landing on the water, but mainly because of their greater internal volume.
Together with the increase in size, the operational speed of the aircraft will also increase (in the event of a crash of another engine during flight), as well as during flights in the stratosphere. Achieving top speed in 850 km / h in five years is considered quite real. By the same date, the normal operating altitude of flights will reach 6500 — 8 500 m. The altitude of flights in 15000 — 18 000 m will be carried out only by military aircraft and, possibly, for scientific purposes. The height of the same order 30000 m can never be achieved by modern types of aircraft heavier than air. A higher ceiling of the aircraft itself allows for greater speed; in addition, it also improves navigation due to the presence of relatively better weather in the stratosphere. Huge airplanes require resolution of airborne sustainability and control problems. At present, manual control is somewhat facilitated by the aerodynamic balance of the controlled surfaces of the aircraft. If the size of the aircraft will increase dramatically, then manual control will become impossible and you will need hydraulic control. Automatic control will also be not only useful in this case, but also essential.
Regarding the aerodynamics of the aircraft of the future, current trends are already talking about further improvements. Modern aircraft have the following main features; low wing, retractable landing gear with a well-streamlined base, all-metal construction, hidden frame, split flap, improved propellers and increased specific power of the motors.
Further improvements will be in propellers with variable pitch, covering the holes of retractable landing gear, removing outdoor antennas, improving stability and control, using exhaust gases (heat) for supercharging and heating.
The constructive weight of the aircraft tends to be facilitated by improving materials, increasing knowledge of the application of loads, better placement of structural elements and increasing the size of the aircraft themselves.
Wind load with an increase in the size of the aircraft in the future as a percentage of the total weight will remain the same. With an increase in the total weight, the body of the aircraft will be lightened, engine sockets will relatively shrink with the weight of the body, and the body itself will be relatively lighter with increasing sizes.
Installed aircraft equipment as a percentage of the total weight will remain the same. For example, for flying boats weighing in 9 tons it will take 6%, and for an aircraft in 45 tons - 4% plumb. The weight of the hull of the flying boat will consistently be reduced by 1% - 2% with an increase in the total weight for every 4,5 tons.
The dirigible building of the near future will also make a big step forward. It can be said that the regular trans-ocean service of hard airships will be already a past stage and will develop into even more responsible flights. If now aircrafts are heavier than air, they are still being adapted for passenger flights across the ocean, then airships have long been working on the Europe-America line. In the coming years, airships will not be forced out by airplanes - they are too valuable additions to other existing types of transport. The further progress of the airship building will consist mainly in increasing the speed and amenities for passengers, but the size of their special growth will not receive. Now the designers are solving an interesting problem of the airship-aircraft carrier, combining the advantages of flying vehicles lighter and heavier than air. High-speed aircraft of such airship-aircraft carrier will be launched from the middle of the ocean for urgent delivery to the coast of mail, express cargo and passengers. Of course, there is no reason to speak of the military value of airship aircraft carriers.
Airship aircraft carrier on the cover of the American magazine "Modern Mechanics" №10, 1934,
It is interesting to note that the American designers are quite confident in the implementation of the five-year "plan" of aviation development predicted by them. They argue that in the more distant future, the field of engineering in the improvement of aircraft will not be narrowed.
But this is an aircraft carrier. "Modern Mechanics", March 1938 of the Year.
Summarizing the statements of US aviation specialists, we list some of the main achievements that should characterize the 1942 aircraft of the year.
Aircraft engines will have a smaller proportion and in all likelihood will not increase in linear dimensions. Air-cooled motors will retain their place, and liquid-cooled motors will be widely developed at high power. Diesel will find its application on airplanes in units of very high power. They, however, are unable to displace spark-ignited engines, which will continue to excel in aviation.
The practice will include more efficient fuel, and its specific consumption will be significantly reduced. It is expected that this reduction in fuel consumption in five years will reach 10%.
The size and quality indicators of aircraft of all types will continue to grow, while the limitation of this growth will be dictated only by the conditions of expediency and profitability, but not by technical difficulties. Apparently, one should expect growth of the total weight of the aircraft from two to three times compared with the largest of the currently existing ones. The speed will also increase, and it will be about 120 — 125% of the speeds already achieved.
Soviet TB-3 with the I-16 fighter suspended under it.
Driving will require an auxiliary control system. Further expansion of the use of automatic control will make significant changes to the requirements for the stability of the aircraft, and in the future it may also require less automatic stability.
The development of aviation is largely common to many countries. It can even be said that aviation technology is international, since it is impossible even to imagine its isolated development in any one country. Turning to the prospects for the development of our Soviet aviation, it should be boldly stated that its achievements in five years will be, in any case, no less remarkable than in America. High Soviet aviation culture to the guarantee.
As proof of this statement, it is quite enough to refer to the modern indicators of our aviation. What are the achievements of the Soviet aircraft and its valiant pilots in the 1942 year, if even now we already have such wonderful aircraft, such as, for example, ANT-25. But this machine was created in 1934 year - our experts consider it now somewhat outdated. For three years, the technician had time to step forward greatly.
Transarctic flights of the Heroes of the Soviet Union vols. Chkalov, Baidukov, Belyakov, Gromov, pilots Yumashev and Danilin on the route Moscow - the North Pole - North America have written a new remarkable page in the history of the development and achievements of world aviation. The power and high level of the Soviet aircraft industry was once again demonstrated. Soviet planes began to fly in the most difficult conditions farthest of all - they will fly in the future and higher and faster than all. "
Fig. A. Shepsa